1. Field of Invention
The present invention refers to 3-indolepyruvic acid derivatives, substituted on the benzene moiety, along with a method for their production and their therapeutic use.
The compounds according to the present invention are characterized by the presence of substituents on the benzene ring of the indole nucleus and are represented by the general formula I ##STR1## in which X is methyl, methoxy, hydroxyl or halogen.
2.Description of the Prior Art
3-indolepyruvic acid has shown itself to possess extraordinary biological and pharmacological activity because, having double bonds conjugated into enole configuration, it is capable of capturing oxygen free radicals (especially OH) and therefore of transforming itself into kynurenic acid, which in international literature appears as the most important physiological antagonist of excitatory amino acids. Said amino acids are substances capable of irreversibly destroying neurons in degenerative diseases, such as cerebral ischemia, aging, epilepsy, etc. (see for example Lancet, II, 140-143, 1985; Neurosience Letters 48, 273-278, 1984).
The properties of 3-indolepyruvic acid as a capturer of free radicals have been described in the published European application No. 0362152.
The capability of 3-indolepyruvic acid to transform itself into kynurenic acid has, on the other hand, been described in the international patent application WO88/09789. In the latter application have also been described several derivatives of 3-indolepyruvic acid, obtained by esterification or amidation of the carboxylic acid.